I don't know so much that it takes a sharp mind, It is more taking advantage of a flaw, and I think it's simple, if you find a league with such a set up simply leave and let it die it's natural death.

You can't use all those hidden gems if you have no competition because your League won't fill.

I was playing for almost 5 months before I learned about switching seasons. This put me at a big disadvantage compared to other owners who were aware of that ability.

I can chalk that up to a pretty underwhelming primer on playing the game, I don't expect to be handed the keys to the kingdom from day one, but crawling around in the dark and wondering what the heck happened is even more frustrating, and only a few folks will share that type of information - the rest like that I was uninformed, makes them feel smarter, that they have an unfair advantage, this site REALLY does need a better section for new owners if it wants to grow

The only way I discovered it was by seeing a guy I almost drafted as a 66 on another team as an 83, I was like what the hell is that? I thought they were cheating or something, but no, they had swapped a season is all.

It's funny that in Auto leagues a players Best Offensive season is selected - but in Custom leagues if the commissioner wants to be a dick he can change how a player is shown by changing his season, then draft him and take advantage, that's kind of shady too.
Fortunately the Custom league I am in has an honest and fair commissioner who don't play that crap.